• 대한전자공학회논문지SP
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• 제38권3호
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• pp.247-257
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• 2001

일반적 칼라 출력 장치는 제한된 범위의 색만을 재현 할 수 있다. 특히 프린터와 같이 색의 재현성이 부족한 장비에서는 하드웨어 특성에 따른 채색 면적이나 인쇄에 사용되는 용지의 특성에 따라 염료의 확산 등에 대해서도 고려해야 한다. 특히, 색을 프린트하기 위해서는 출력 과정에서 색의 선형적인 증가와 감소가 이루어져야 하며 또한 정확한 색의 모델링이 가능하여야 한다. 따라서 본 논문에서는 이를 위해 프린터 출력시 실제 채색 면적과 시각적 색감을 고려할 수 있는 디더링 방법을 제안한다. 제안된 방법은 실제 채색 면적을 고려한 패턴 데이터 베이스를 만들어 이를 디더링 패턴으로 이용하게 된다. 그리고 이 데이터 베이스에서 정확한 패턴을 선택하기 위해서는 인간시각의 색 인지력을 모델링한 대조 민감도 함수를 사용하게 된다. 따라서 본 논문에서는 저해상도의 칼라 출력장치에서도 고화질의 색을 재현할 수 있게 해준다.

• 대한의용생체공학회:의공학회지
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• 제19권4호
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• pp.351-360
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• 1998

아날로그 감마카메라에 비해 디지털 카메라는 Q.C가 편리하고, Calibration과 조작이 매우 쉬운 장점들을 갖고 있어 영상 질을 향상시킬 뿐만 아니라 진단의 정확도를 높일 수 있다. 더욱이, 디지털 카메라로 획득한 디지털 영상은 PACS(Picture Archiving and Communication System) 뿐만 아니라 원격진료에도 활용될 수 있다. 그러나, 많은 병원들이 아직도 아날로그 카메라를 사용하고 있고 이들을 디지털 카메라로 대체하기는 어려운 상황에 있다. 본 연구는 아날로그 감마카메라를 디지털화 할 수 있는지의 가능성을 보는 것이었다. 카메라를 디지털화 한 후 균일도 계수능력 등의 물리적 특성을 측정하였다. 임상에서의 사용 가능성을 보기 위해 아날로그 시스템과 디지털 시스템을 동시에 연결하여 임상 데이터들을 획득하였다. 이들의 결과는 임상환경에서 아날로그 카메라를 디지털화 하 수 있다는 가능성을 보여주었다.

• 한국환경교육학회지:환경교육
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• 제25권1호
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• pp.25-34
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• 2012

Following the UN Conference on Environment and Development held in Rio de Janeiro, Brazil, in 1992, a number of companies began to incorporate the concept of Environmental Sustainability into their business activities. Soon after this, interest in business sustainability within the academic world began to grow and a number of universities in Europe and North America decided to develop environmental management education-related materials and curricula under the support from their respective govemments and private companies. Starting in 1996, a wide-range of environmental management education programs also began to appear in several Korean universities. However, in contrast with the gradual evolution of environmental management education into a single study field internationally, environmental management education in Korea has not become fully specialized, nor has it developed in a systematic manner. In order to enhance and facilitate domestic environmental management education in Korea, universities must put more effort into differentiating environmental management education courses from regular environmental courses through the development of curricula related to business management. The business world has an immense impact on the environment and international environmental regulations are steadily becoming stronger. In this light, environmental education programs need to extend their sphere of study not only to the spread of knowledge and sensitivity towards the environment among members of the general public, but also train businessmen to have an understanding of how their actions impact the environment.

• Journal of Korean Neurosurgical Society
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• 제30권2호
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• pp.186-193
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• 2001

Objectives : Trigeminal neuralgia and hemifacial spasm are caused by vascular compression of the REZ(root entry or exit zone) of the 5th and the 7th cranial nerve. Preoperative detection of neurovascular compression is essential for accurate diagnosis, appropriate treatment, and the good operative results. Three dimensional Fourier Transformation-Constructive Interference in Steady State(3DFT-CISS) images are known to give good contrast between CSF, nerve, and vessels. We applied a 3DFT-CISS imaging technique for the preoperative evaluation of patients with these diseases and estimated the diagnostic accuracy and usefulness of this study. Methods : A series of 71 patients with trigeminal neuralgia and hemifacial spasm were treated by microvascular decompression. Among them 34 patients with trigeminal neuralgia and 24 patients with hemifacial spasm had preoperative CISS images. We compared the radiologic finding with the operative finding, and analysed the diagnostic usefulness of 3DFT-CISS imaging. Results : The sensitivity of CISS images of detecting the neurovascular compression was 90.3% in trigeminal neuralgia and 100% in hemifacial spasm. There were one false-positive and three false-negative cases in trigeminal neuralgia, and one false-positive case in hemifacial spasm. The accuracy in diagnosing the causative vessel was 73.5% in trigeminal neuralgia and 83.3% in hemifacial spasm. Conclusion : CISS image is very useful diagnostic tool for preoperative evaluation of neurovascular compression in patients with trigeminal neuralgia and hemifacial spasm. No additional neuroradiologic examination other than CISS image and MRA is needed for preoperative evaluation of patients with trigeminal neuralgia and hemifacial spasm.

• 한국자기학회지
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• 제8권6호
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• pp.388-394
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• 1998

자성물질의 자기이방성을 측정하기 위해 개선된 구조의 null-type 토크마그네토미터를 설계, 제작하였다. 제작된 토크마그네토미터의 측정범위는 $0~{\pm}15\;dyne.cm$이며 조절이 가능하다. 이 범위내에서 분해능은 약 0.0005 dyne.cm 정도이며, 1회 측정시 잡음수준은 ~0.01 dyne.cm, 10회 반복측정한 경우 ~0.004 dyne.cm 이하였으며, 반복재현시 나타나는 오차는 0.5% 이하였다. 본 연구에서 제작된 토크마그네토미터는 종전의 null-type 토크마그네토미터와는 달리 영구자석을 내부에, 헬름홀쯔 코일을 외부에 위치시킨 구조의 토크미터를 포함하고 있다. 이로 인하여, 기하학적으로 등방적인 모양으로 토크미터를 설계할 수 있었으며, 헬름헬쯔 코일의 입력전선과 출력전선의 역학적 및 전기적 임피던스에 으히나 토크곡선의 왜곡을 방지할 수 있었고, 샘플막대의 관성모멘트를 줄일 수 있었다. 그 결과 토크에 대하 보다 민감하면서도 반응속도가 빠르며 토크곡선의 왜곡요인이 적은 토크마그네토미터를 제작할 수 있었다.

• 한국환경교육학회지:환경교육
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• 제15권1호
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• pp.137-147
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• 2002

The progress of environmental science and technology in the developed countries has been rapid in recent years. Particularly remarkable has been the advancement of various pollutant control measures, which have brought the pollution of inorganic factors such as air and water under control. In contrast, diversity of the ecosphere, of which man is a part, is being steadily Impoverished and the biological community is getting unvaryingly uniform. These phenomena were brought about by the expansion of artificial environment such as new industrial complexes, transportation facilities and urban development. Man has constructed uniform and artificial environment, believing in the premise of confrontation with nature, to such a scale that the natural environment and biological community have lost their balance. This will increasingly endanger the soundness of the biotic environment of nature, which constitutes the potential foundation both for the survival environment of man as biological entity and for the development of human civilization. In order to guarantee the soundness of man's body, intelligence and sensitivity as wholesome gene Pool on the earth and for the future of man, primarily important environmental education is the understanding of how man can everlasting exist in and with the survival environment. In view of this reality, it is vitally important to create ecologically diverse and well-balanced environment with living materials, i.e., vegetation in order to secure lasting survival environment for man. This task is urgently required in highly artificial environment where non-biological materials have forced the impoverishment of the biological community. Therefore, environmental education for the future should not be totally oriented to technology as that in the past nor it is limited to the medical aspect where well-being of human is the sole object of concern. That is to say, environmental education for the future should be one that provides knowledge that human can understand his place based on the ecological concept and thereby make him to have ethical consciousness that he can control his behavior within the reasonable level for ecological niche who he is located.

• 한국컴퓨터정보학회논문지
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• 제26권11호
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• pp.191-199
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• 2021

본 연구는 노인운전자의 운전 면허를 갱신 할 때 필요한 추가 검사를 제안할 목적으로 실시되었다. 우리나라에서는 고령 인구가 빠르게 증가하면서 고령 운전자의 비율이 높아지고 있다. 전반적으로 교통사고율이 감소하고 있지만, 고령 운전자에서는 교통사고율과 교통사고로 인한 사망률이 증가하고 있다. 본 연구에서는 우리나라에서 실시하고 있는 고령 운전자의 운전면허 갱신 시 실시하고 있는 검사와 교육을 알아보고 외국의 현황과 비교하여 필요한 검사를 알아보기 위해 시행했다. 운전능력과 관련된 신체기능은 크게 시각, 인지, 운동 및 체성감각의 세 영역에 대해 평가하는 것이 적절하지만, 현재 우리나라에서는 시각 중 시력만을 평가하고 있고, 인지 영역에서는 경증 인지 손상은 알아볼 수 없는 MMSE-K와 시계 그리기 검사만을 진행하고 있다. 운전을 수행하는 운동능력에 대해서는 전혀 평가하고 있지 않다. 따라서 고령 운전자의 안전운전을 위해서는 운전면허 갱신 시 실시하는 검사에 시각에서는 시야와 대조대비력 검사, 인지 기능에서는 경증 인지장애를 구별할 수 있는 검사, 운동기능을 평가하기 위한 검사를 보완해야 할 것이다.

• Experimental Neurobiology
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• 제26권5호
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• pp.241-251
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• 2017

Saturation mutagenesis was performed on a single position in the voltage-sensing domain (VSD) of a genetically encoded voltage indicator (GEVI). The VSD consists of four transmembrane helixes designated S1-S4. The V220 position located near the plasma membrane/extracellular interface had previously been shown to affect the voltage range of the optical signal. Introduction of polar amino acids at this position reduced the voltage-dependent optical signal of the GEVI. Negatively charged amino acids slightly reduced the optical signal by 33 percent while positively charge amino acids at this position reduced the optical signal by 80%. Surprisingly, the range of V220D was similar to that of V220K with shifted optical responses towards negative potentials. In contrast, the V220E mutant mirrored the responses of the V220R mutation suggesting that the length of the side chain plays in role in determining the voltage range of the GEVI. Charged mutations at the 219 position all behaved similarly slightly shifting the optical response to more negative potentials. Charged mutations to the 221 position behaved erratically suggesting interactions with the plasma membrane and/or other amino acids in the VSD. Introduction of bulky amino acids at the V220 position increased the range of the optical response to include hyperpolarizing signals. Combining The V220W mutant with the R217Q mutation resulted in a probe that reduced the depolarizing signal and enhanced the hyperpolarizing signal which may lead to GEVIs that only report neuronal inhibition.

• 한국미생물·생명공학회지
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• 제50권1호
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• pp.147-156
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• 2022

Urinary tract infections (UTIs) are one of the most common infections in different age groups, including children. Bacteria are the main etiological agents of UTIs. The aim of the present study was to isolate, identify, and determine the antibiotic susceptibility of bacteria isolated from children with UTIs from Baghdad, Iraq. Three hundred and two urine samples were collected from children aged 6 months to 12 years. The samples were cultured on blood agar and MacConkey agar. The selected colonies were subjected to biochemical tests and antibiotic susceptibility analysis using the Vitek^® 2 Compact automated microbial identification system. In this sample, 299 bacteria were identified, of which, 267 were gram-negative bacteria, and 32 were gram-positive bacteria. Escherichia coli (56%) was the most commonly isolated gram-negative bacteria, followed by Pseudomonas aeruginosa (14%), Enterobacter spp. (10.48%), Klebsiella pneumoniae (9.36%), Proteus spp. (7.8%), Acinetobacter baumannii (1.5%), and Morganella morganii (0.37%). Enterococcus faecalis (62.5%) was the most commonly detected gram-positive bacteria, followed by Staphylococcus aureus (37.5%). E. coli and P. aeruginosa were the most antibiotic-resistant bacteria. Among the tested antibiotics, meropenem showed 100% sensitivity, followed by imipenem (97.4%), amikacin (91.8%), and tobramycin (83.5%). In contrast, the high frequencies of resistance were observed with cefixime (93.2%), cefotaxime (78.7%), and ceftriaxone/cefotaxime (71.2%). In conclusion, carbapenems and aminoglycosides are highly recommended for the empirical treatment of UTIs, while, Quinolones, penicillins, and cephalosporins are not suggested. Frequent antibiotics susceptibility testing are warranted to determine the resistance pattern of UTI bacteria.

• 대한방사선기술학회지:방사선기술과학
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• 제45권1호
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• pp.1-9
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• 2022

In this study, we proposed an image quality control for an automatic exposure control (AEC) of digital radiographic imaging system and tried to analyze the performance of the AEC by various manufacturer. The subjects of the experiment were analyzed for the AEC image quality evaluation using digital radiation generators from four manufacturer such as PHILIPS, GE Healthcare, SAMSUNG Healthcare, DK Medical Solution. We used as materials for the implementation of the image quality evaluation by coins (500 won, KOMSCO, Korea). This study evaluated the performance evaluation of the AEC as image quality and exposure dose (Milliampere-seconds; mAs). The image quality evaluation was tried visual assessment by two radiologic technologists and contrast to noise (CNR) by ImageJ. The exposure dose investigated mAs on digital radiation generators. The radiographic coin images acquired 360 images based on change in the control factors of the AEC, which were kVp, the consistency of field configuration and dominant zone, sensitivity and density. As a result, there was a significant difference in the AEC performance between manufacturer. The CNR by the AEC for each manufacturer showed a difference of up to about 1.9 times. The exposed tube current by the AEC for each manufacturer showed a difference of up to about 5.8 times. It is expected that our proposed evaluation method using coins could be applied as the AEC performance evaluation method in the future.